Add, change, Rename and Remove a Remote in Git

To add a remote link to the existing repo:

git remote add <remote_name> <remote_link>

Example:

git remote add o1 <git_url>

To change the remote url of the remote added.:

git remote set-url origin https://github.com/USERNAME/REPOSITORY.git

To remove the remote.:

git remote rm destination

To rename the remote:

git remote rename origin destination

Reference:
changing-a-remotes-url
removing-a-remote
renaming-a-remote